# Search results

1. ### Electric Potential and a Conductor

Hmm interesting. I've got it now. The electric potential inside the shell is the sum of the electric potential on the outer edge and the inner edge. This yields: V=k\frac{3Q}{4r_1} Ok, but I'm still confused on the next question. I would think the electric potential inside the cavity would...
2. ### Electric Potential and a Conductor

Never mind, what that tells me is that the electric potential inside the conductor is constant, but how do I derive the value?
3. ### Electric Potential and a Conductor

Yes, I know that vec(E)=-vec(\nabla V) I also know that E=-\frac{dV}{ds} when ds||E If I use the second equation I set E equal to zero and you have v=0 which is wrong. The first one I'm not even sure how to use since I have magnitudes of vectors not vectors.
4. ### Electric Potential and a Conductor

Homework Statement A hollow spherical conductor, carrying a net charge +Q, has inner radius r1 and outer r2=2r1 radius (see the figure ). At the center of the sphere is a point charge +Q/2. A.Write the electric field strength E in all three regions as a function of r: for r>r2,r1<r<r2...
5. ### Coulomb's Law and potassium

Homework Statement An electron is separated from a potassium nucleus (charge 19e) by a distance of 5.2 X 10-10m. what is the electric force between these particles? (e = 1.60 X 10-19C, Kc= 8.99 X 109 N*m2/C2) Homework Equations Felectric= Kc[(q1)(q2)/r2] The Attempt at a Solution...
6. ### Initial Velocity

they're equal
7. ### Initial Velocity

I'm sorry but I don't know how you would combine these equations. I have tried to combine them but I come up with an answer that you wouldn't be able to solve for the v^2 and dosent seam logical. K.E=(1/2)(m)(v^2) P.E.= mgh P.E/(G)(H)=m K.E=(1/2)[P.E/(G)(H)](v^2)...
8. ### Initial Velocity

Yeah, your right. I meant to put K.E.= (1/2)(m)(v^2) I still don't understand what I'm suppose to do. Both equations require mass to solve for the potential or kinetic energy. Does mass matter in this problem because I don't think I can solve for the mass of the cannonball?
9. ### Initial Velocity

Homework Statement A cannon shoots straight up into the air a cannonball which reaches a maximum height of 600m. What was the initial velocity of the cannonball when it was fired from the cannon. (Note: this problem contains all the information necessary to be solved.) use g=10m/s^2...
10. ### Potential Energy

Thanks, So, if I correct my units I would have: P.E.= mgh P.E.=(2kg)(10m/s^2)(500m) P.E.= 10000 joules P.E. elastic= (1/2)(k)(x^2) k= P.E elastic/ (1/2)(x^2) k= 10000/ (1/2)(1) k=20000 N/m ? Is this correct?
11. ### Potential Energy

Homework Statement A spring is compressed a distance of 1m and a 2 kg rock is shot straight up with the spring. The rock attains a maximum height of 500m. What is the force constant k of the spring? Use g=10m/s^2 Homework Equations P.E.= mgh P.E. elastic= (1/2)(k)(x^2) The Attempt...